caster, camber, and toe-in

Discussion in 'The whoa and the sway.' started by danhei, Oct 14, 2004.

  1. danhei

    danhei Well-Known Member

    Hey Guys,

    It's been awhile since I've posted but I've been busy with my car. Just got it painted (white) last week so that's exciting for me.

    Well, disk brakes are next and before we start that I'd like to know the original specs for the caster, camber, and toe-in so we can try to keep the suspension geometry close to stock.

    Any help is appreciated.

    Thanks.
     
  2. 70 gsconvt

    70 gsconvt Silver Level contributor

    Here's a good article on swapping on discs all around. There are also several threads here with good info on swapping disc brake onto the front and the rear. Sorry, but can't help on the alignment specs.

    http://www.oldsmobility.com/discbrakes.htm
     
  3. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Dan,
    Here's a chart from my 70 Chassis manual. Kind of hard to read. Caster preferred setting is -1/2* (+ or - 1/2*), 0-1* range, 1* side to side variation permitted. Camber preferred setting is +1/2* (+ or - 1/2*), +1*-0* range, 1* variation side to side permitted. Toe in 3/16" (+ or - 1/16") preferred, range 1/8"-1/4". A more performance alignment would have 3-3 1/2* + caster, -1/2* camber, and 1/16" toe in. With the stock A body front suspension, as the suspension travel goes from full extension to full compression, the camber goes positive. The outside tire in a turn (where suspension would be compressed) would have + camber, and the tire tends to roll onto the sidewall, and slip. The opposite happens to the inside tire. This is why our cars understeer moderately when pushed hard into a turn. Big swaybars minimize this effect. Dialing in - camber also helps in this regard. The more positive caster you run, the better the car will track at speed. Positive caster also induces a camber change as the wheels go from straight to full lock. The outide tire in a turn would have increasing - camber as you turn the steering. Mercedes Benz uses like 10* positive caster. If you have ever seen a Benz parked with it's wheels at full lock, you can actually see one tire tilted out at the top, and the other tilted in. Mercedes Benz are some of the best handling cars in the world. Anyway, maybe more info than you needed :laugh:
     
  4. gstewart

    gstewart Well-Known Member

    seems to me that one of the fellows suggested changing the camber, caster, toe (one or all) if u install radial tires .
     
  5. danhei

    danhei Well-Known Member

    Thanks for the help, Larry. I guess it's pretty easy to change the camber and toe-in but I'm not sure how easy it would be to change the caster. I will be running a 1.25" swaybar off a Trans-Am so that should help. Probably will start the brake swap this weekend as well as new bushings, ball joints, shocks, and springs. Hopefully I'll have a pretty decent handling car when all is done.

    Dan
     
  6. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Dan,
    Actually it's very easy. If you don't have a Buick chassis manual, you should get one. Explains everything very well. According to the manual, to make camber more -, add an equal shim amount to both bolts. By adding a pack of shims .090" to each bolt, camber will be reduced by 1/2*. To make caster more positive, remove a shim amount from the front bolt, and add an equal amount of shims to the rear bolt. If you remove .030" from the front bolt, and add it to the rear bolt, caster will increase(more +) by 1/2*. If you set up your camber first, you can change the caster(without affecting your camber)
     
  7. CJay

    CJay Supercar owner Staff Member

    Yes, but too much caster and you will get tire scrub on tight turns. My recommendation is to just adjust it to factory specs. Be sure to notice the "SAI" (steering axis inclination) and "included angle" readings on both sides. That will let the alignment tech know of any front end parts are bent. Also have him check the "TOOT". Toe out on turns. That will check to make sure that both steering arms on the spindles arent bent at all. Some alignment techs dont understand or care about these readings.

    Jason
     
  8. 12lives

    12lives Control the controllable, let the rest go

    alignment

    I had an interesting experience a few months back. I had replaced all the bushings, ball joints, and links on my 70 GS front end and got it aligned to the factory specs. I was not very happy as it had a "dead" spot in the middle when going straight. About the same time Marco was getting radial tires for his GS and Jim Hise (?) and Larry helped him with the specs. Since I was running radial tires also, I used the same specs and had the alignment redone. It made a BIG difference :beer and the car handles better and feels better. So with a back to back comparison on the same car, I have to agree with Larry and Jim on the specs. Unfortuately that thread was lost in the Hacker attack.....but Larry summarized it well above.
    +2.5 caster, -1/8 camber, and 1/16 toe.....

    - Bill :TU:
     

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